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Friday, August 17, 2018

Which of the following RegEx character sets does the '\w' meta-character most closely represent in Perl-compatible Regular Expression implementations?

Which of the following RegEx character sets does the '\w' meta-character most closely represent in Perl-compatible Regular Expression implementations?

  • [a-zA-Z0-9_]
  • [a-zA-Z]
  • [a-zA-Z0-9]
  • [a-zA-Z_] 

 
Which of the following RegEx character sets does the '\w' meta-character most closely represent in Perl-compatible Regular Expression implementations?

EXPLANATION

The "word" meta-character \w in RegEx will match the full alpha-numeric range, basically the full alphabet as well as number characters, and includes underscores.

Note that it matches more alphabet characters than the standard a through z: pretty much any alphabet character, such as 'ñ', also match.

http://www.w3schools.com/jsref/jsref_regexp_wordchar.asp
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Thursday, August 16, 2018

What is the primary difference between LED and an LCD monitor?

What is the primary difference between LED and an LCD monitor?

  • price
  • Backlighting source
  • Doesn't last as long as plasma displays
  • screen size 

 
What is the primary difference between LED and an LCD monitor?

EXPLANATION

LCD
LCD is the abbreviation of Liquid Crystal display. There are two layers of glass in this technology that are joined together with liquid crystals in between. These crystals help pass or block the light. However, crystals do not produce any light and it comes through fluorescent lamps (CCFL) situated at the back of the screen.
LED
The technology in LED TV’s is much the same with the difference being the source of light at the back of the screen. Whereas it is CCFL in the case of LCD, there is Light emitting Diodes (LED’s) in the case of LED TV’s.
http://www.differencebetween.com/difference-between-lcd-and-vs-led-monitor/
http://www.diffen.com/difference/LCD_TV_vs_LED_TV
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Where does Cryptolocker execute from on a Windows OS?

Where does Cryptolocker execute from on a Windows OS?

  • Desktop
  • C:\Programfiles
  • C:\Windows\System32
  • C:\Users\*User*\AppData\Local 

Where does Cryptolocker execute from on a Windows OS?

EXPLANATION

Cryptolocker runs from App Data Local and starts locking each file from A to Z then works on mapped drives from A to Z.

SOURCE

https://malwaretips.com/blogs/remove-cryptolocker-virus/
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Tuesday, August 14, 2018

What is the default port used by Postfix?

What is the default port used by Postfix?

  • 25
  • 45
  • 37
  • 20 

 
What is the default port used by Postfix?

EXPLANATION

Postfix is an open source mail transfer agent (MTA) that is used to route and deliver emails. Postfix is the alternate of widely
used Sendmail MTA. Postfix uses port number 25 (SMTP) by default.

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Monday, August 13, 2018

What type of RAID is RAID 2?

What type of RAID is RAID 2?

  • Byte-level striping with dedicated parity.
  • A striped set from a series of mirrored drives.
  • Block-level striping with dedicated parity.
  • Bit-level striping with dedicated Hamming-code parity. 

EXPLANATION

RAID 2
RAID 2 consists of bit-level striping with dedicated Hamming-code parity. All disk spindle rotation is synchronized and data is striped such that each sequential bit is on a different drive. Hamming-code parity is calculated across corresponding bits and stored on at least one parity drive. This level is of historical significance only; although it was used on some early machines (for example, the Thinking Machines CM-2), as of 2014 it is not used by any commercially available system.
RAID 2

SOURCE

https://en.wikipedia.org/wiki/Standard_RAID_levels#RAID_2 
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Friday, August 10, 2018

In Linux system, which command will print the output of log file in reverse ?

In Linux system, which command will print the output of log file in reverse ?

  • less
  • cat
  • tac
  • rcs 

 
In Linux system, which command will print the output of log file in reverse ?

EXPLANATION

Let's assume that we have a log file named "Letters" that contains: A B C D (in separate lines).
To view the content of the log file in Linux terminal, the command will be:
linux@machine:~$ sudo cat Letters
And we will get the output:
A
B
C
D

To view the content of the log file in reverse, the command will be:
linux@machine:~$ sudo tac Letters
And we will get the output:
D
C
B
A




SOURCE

https://www.tecmint.com/learn-linux-cat-command-and-tac-command/
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Thursday, August 9, 2018

While working on an issue on a clients network you learn that you will be using the 1000BaseCX standard. What type of cable will you be using.

While working on an issue on a clients network you learn that you will be using the 1000BaseCX standard. What type of cable will you be using.

  • CoreXtended Fiber
  • Single-mode fiber
  • Multimode fiber
  • STP

While working on an issue on a clients network you learn that you will be using the 1000BaseCX standard. What type of cable will you be using.

EXPLANATION

The 1000BaseCX standard specifies Gigabit Ethernet over STP cabling.
  1. Multi-mode Fiber is incorrect because 1000BaseSX and 1000BaseLX specify Gigabit Ethernet over two types of Multi-mode fiber.
  2. Single-mode fiber is used with 100BaseFX standard.
  3. As far as CoreXtended Fiber, there anin't no such animal.

SOURCE

http://www.thenetworkencyclopedia.com/entry/1000basecx/
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